Determine the boot mode of an EC2 instance
The boot mode of an instance is displayed in the Boot mode field in the Amazon EC2 console, and by the
currentInstanceBootMode parameter in the AWS CLI.
When an instance is launched, the value for its boot mode parameter is determined by the value of the boot mode parameter of the AMI used to launch it, as follows:
-
An AMI with a boot mode parameter of
ueficreates an instance with acurrentInstanceBootModeparameter ofuefi. -
An AMI with a boot mode parameter of
legacy-bioscreates an instance with acurrentInstanceBootModeparameter oflegacy-bios. -
An AMI with a boot mode parameter of
uefi-preferredcreates an instance with acurrentInstanceBootModeparameter ofuefiif the instance type supports UEFI; otherwise, it creates an instance with acurrentInstanceBootModeparameter oflegacy-bios. -
An AMI with no boot mode parameter value creates an instance with a
currentInstanceBootModeparameter value that is dependent on whether the AMI architecture is ARM or x86 and the supported boot mode of the instance type. The default boot mode isuefion Graviton instance types, andlegacy-bioson Intel and AMD instance types.
